Windows 7: Seagate Tries for Hybrid Hard Drives Again With Momentus XT

Complete redesign combines speed with affordability



The company calls it a Solid State Hybrid Drive, and it will be available exclusively in a 2.5-inch form factor. There are 250, 320, and 500GB models, all of which feature 32MB of DRAM cache and a 4GB single-layer cell NAND flash cache. There will unfortunately not be any 6Gbps SATA support, despite the XT moniker.

The secret sauce this time is what Seagate calls "Adaptive Memory". The firm has developed new algorithms based on their years of research and producing firmware for regular drives. These algorithms monitor data access transactions over time, and will place a copy of the most frequently accessed data (such as Windows system files) onto flash storage. A table also keeps track and counts of how frequently data is used in order to prioritize it for retention and caching.

This is similar in concept to Microsoft's ReadyBoost, but uses much faster SLC rather than the sluggish commodity NAND that ended up being used in USB flash drives and SD cards. The algorithms are also much more advanced, as is the garbage collection and firmware. Seagate developed its own proprietary NAND flash controller specifically for the Momentus XT.

Conclusion:

The Seagate Momentus XT has been dubbed around the net as a SSD killer. Would I call it that? No, but what I would call it an HDD killer. The Momentus XT beats out traditional hard drives in just about every test. This drive is the perfect stepping stone for those who want the increased speed that a SSD provides, but require more space than current SSD's can deliver (and be cost effective). The best part of the Momentus XT is that with the intelligence of the hardware, the more you work with it, the more it will learns your habits, and the faster it gets. There is no other drive currently on the market that does this and does it well.

With the scores aside, benchmark numbers aren’t always truly representative of what you see in everyday performance. One measure of this drive’s speed is the boot up process. My PC starts up 13 seconds faster than with the traditional hard drive. In addition to the faster boot, it's more efficient at running frequently used programs such as Photoshop, games and day to day applications, making them nice and snappy.

I was fortunate enough to actually start testing the Hybrid back in the alpha stages of its design and I quickly came to realize the potential it had. In fact, I received the Momentus XT alpha drive before ever touching an SSD for review and I must admit, I prefer the capacity and snappiness of the Momentus XT drive to any of the SSD's that I own. Now that I have two of them in a RAID setup, I would not spend the extra money on another SSD. As long as I can have the speed and capacity of the Momentus XT, I'll pick one over an SSD every time.

Because of the nature of this type of technology, I took the opportunity to speak with some of the Seagate engineers during the testing and one question that was eating at my mind is: "What happens if the SSD portion of the drive fails?" Everyone with important documents and photos does not want to be left fighting for our data. The engineers assured me that in the unlikely event the SSD fails, then the algorithm accounts for the loss and it only stores the data on the physical drive. They also commented that the information stored on the SSD portion is mirrored on the physical drive as well, so no data will be lost with a failure of the SSD. In essence the device would act just like any other mechanical drive from that point forward.

Right now, a 128GB SSD will run you an about $300, but the Seagate Momentus XT will have a MSRP of ~ $156 for the 500GB drive we tested here. So for the price of one 128GB SSD, you can purchase two Momentus XT drives, run them in a RAID 0 configuration, almost match the speed, and get eight times the storage. I don't know about you, but a terabyte of storage with speeds almost as fast an SSD, sure sounds great to me. When it comes to buying a hard drive, I look for price and for performance. On that note, I’m very impressed with Momentus XT. It’s been great testing this new device and I definitely recommend it.